# Solar eclipse of September 11, 1988

An annular solar eclipse occurred at the Moon's descending node of orbit on Sunday, September 11, 1988, with a magnitude of 0.9377. A solar eclipse occurs when the Moon passes between Earth and the Sun, thereby totally or partly obscuring the image of the Sun for a viewer on Earth. An annular solar eclipse occurs when the Moon's apparent diameter is smaller than the Sun's, blocking most of the Sun's light and causing the Sun to look like an annulus (ring). An annular eclipse appears as a partial eclipse over a region of the Earth thousands of kilometres wide. Occurring only 12.5 hours after apogee (on September 10, 1988, at 16:10 UTC), the Moon's apparent diameter was smaller.
Annularity was visible in southeastern Somalia (including the capital city Mogadishu), the Indian Ocean and Macquarie Island of Australia. A partial eclipse was visible for parts of East Africa, the Middle East, South Asia, Southeast Asia, Australia, and New Zealand.

## Eclipse details

Shown below are two tables displaying details about this particular solar eclipse. The first table outlines times at which the moon's penumbra or umbra attains the specific parameter, and the second table describes various other parameters pertaining to this eclipse.
September 11, 1988 Solar Eclipse Times :
| Event | Time (UTC) |
| First Penumbral External Contact | 1988 September 11 at 01:46:36.7 UTC |
| First Umbral External Contact | 1988 September 11 at 02:56:30.0 UTC |
| First Central Line | 1988 September 11 at 02:59:28.7 UTC |
| First Umbral Internal Contact | 1988 September 11 at 03:02:28.6 UTC |
| Greatest Duration | 1988 September 11 at 04:35:51.5 UTC |
| Greatest Eclipse | 1988 September 11 at 04:44:28.7 UTC |
| Ecliptic Conjunction | 1988 September 11 at 04:50:04.6 UTC |
| Equatorial Conjunction | 1988 September 11 at 05:15:01.8 UTC |
| Last Umbral Internal Contact | 1988 September 11 at 06:26:09.7 UTC |
| Last Central Line | 1988 September 11 at 06:29:09.8 UTC |
| Last Umbral External Contact | 1988 September 11 at 06:32:08.7 UTC |
| Last Penumbral External Contact | 1988 September 11 at 07:42:08.2 UTC |
September 11, 1988 Solar Eclipse Parameters :
| Parameter | Value |
| Eclipse Magnitude | 0.93768 |
| Eclipse Obscuration | 0.87924 |
| Gamma | −0.46811 |
| Sun Right Ascension | 11h18m19.4s |
| Sun Declination | +04°29'02.7" |
| Sun Semi-Diameter | 15'53.3" |
| Sun Equatorial Horizontal Parallax | 08.7" |
| Moon Right Ascension | 11h17m30.7s |
| Moon Declination | +04°06'57.9" |
| Moon Semi-Diameter | 14'42.2" |
| Moon Equatorial Horizontal Parallax | 0°53'57.6" |
| ΔT | 56.1 s |

## Eclipse season

This eclipse is part of an eclipse season, a period, roughly every six months, when eclipses occur. Only two (or occasionally three) eclipse seasons occur each year, and each season lasts about 35 days and repeats just short of six months (173 days) later; thus two full eclipse seasons always occur each year. Either two or three eclipses happen each eclipse season. In the sequence below, each eclipse is separated by a fortnight.
Eclipse season of August–September 1988 :
| August 27 Ascending node (full moon) | September 11 Descending node (new moon) |
| Partial lunar eclipse Lunar Saros 118 | Annular solar eclipse Solar Saros 144 |

## Related eclipses
### Eclipses in 1988

* A penumbral lunar eclipse on March 3.
* A total solar eclipse on March 18.
* A partial lunar eclipse on August 27.
* An annular solar eclipse on September 11.

### Metonic

* Preceded by: Solar eclipse of November 22, 1984
* Followed by: Solar eclipse of June 30, 1992

### Tzolkinex

* Preceded by: Solar eclipse of July 31, 1981
* Followed by: Solar eclipse of October 24, 1995

### Half-Saros

* Preceded by: Lunar eclipse of September 6, 1979
* Followed by: Lunar eclipse of September 16, 1997

### Tritos

* Preceded by: Solar eclipse of October 12, 1977
* Followed by: Solar eclipse of August 11, 1999

### Solar Saros 144

* Preceded by: Solar eclipse of August 31, 1970
* Followed by: Solar eclipse of September 22, 2006

### Inex

* Preceded by: Solar eclipse of October 2, 1959
* Followed by: Solar eclipse of August 21, 2017

### Triad

* Preceded by: Solar eclipse of November 11, 1901
* Followed by: Solar eclipse of July 13, 2075

### Solar eclipses of 1986–1989

This eclipse is a member of a semester series. An eclipse in a semester series of solar eclipses repeats approximately every 177 days and 4 hours (a semester) at alternating nodes of the Moon's orbit.
Solar eclipse series sets from 1986 to 1989 :
| Ascending node | Ascending node | Ascending node | Descending node | Descending node | Descending node |
| Saros | Map | Gamma | Saros | Map | Gamma |
| 119 | April 9, 1986 Partial | −1.0822 | 124 | October 3, 1986 Hybrid | 0.9931 |
| 129 | March 29, 1987 Hybrid | −0.3053 | 134 | September 23, 1987 Annular | 0.2787 |
| 139 | March 18, 1988 Total | 0.4188 | 144 | September 11, 1988 Annular | −0.4681 |
| 149 | March 7, 1989 Partial | 1.0981 | 154 | August 31, 1989 Partial | −1.1928 |

### Saros 144

This eclipse is a part of Saros series 144, repeating every 18 years, 11 days, and containing 70 events. The series started with a partial solar eclipse on April 11, 1736. It contains annular eclipses from July 7, 1880 through August 27, 2565. There are no hybrid or total eclipses in this set. The series ends at member 70 as a partial eclipse on May 5, 2980. Its eclipses are tabulated in three columns; every third eclipse in the same column is one exeligmos apart, so they all cast shadows over approximately the same parts of the Earth.
The longest duration of annularity will be produced by member 51 at 9 minutes, 52 seconds on December 29, 2168. All eclipses in this series occur at the Moon’s descending node of orbit.
Series members 5–26 occur between 1801 and 2200: :
| 5 | 6 | 7 |
| May 25, 1808 | June 5, 1826 | June 16, 1844 |
| 8 | 9 | 10 |
| June 27, 1862 | July 7, 1880 | July 18, 1898 |
| 11 | 12 | 13 |
| July 30, 1916 | August 10, 1934 | August 20, 1952 |
| 14 | 15 | 16 |
| August 31, 1970 | September 11, 1988 | September 22, 2006 |
| 17 | 18 | 19 |
| October 2, 2024 | October 14, 2042 | October 24, 2060 |
| 20 | 21 | 22 |
| November 4, 2078 | November 15, 2096 | November 27, 2114 |
| 23 | 24 | 25 |
| December 7, 2132 | December 19, 2150 | December 29, 2168 |
| 26 |
| January 9, 2187 |

### Metonic series

The metonic series repeats eclipses every 19 years (6939.69 days), lasting about 5 cycles. Eclipses occur in nearly the same calendar date. In addition, the octon subseries repeats 1/5 of that or every 3.8 years (1387.94 days). All eclipses in this table occur at the Moon's descending node.
22 eclipse events between September 12, 1931 and July 1, 2011 :
| September 11–12 | June 30–July 1 | April 17–19 | February 4–5 | November 22–23 |
| 114 | 116 | 118 | 120 | 122 |
| September 12, 1931 | June 30, 1935 | April 19, 1939 | February 4, 1943 | November 23, 1946 |
| 124 | 126 | 128 | 130 | 132 |
| September 12, 1950 | June 30, 1954 | April 19, 1958 | February 5, 1962 | November 23, 1965 |
| 134 | 136 | 138 | 140 | 142 |
| September 11, 1969 | June 30, 1973 | April 18, 1977 | February 4, 1981 | November 22, 1984 |
| 144 | 146 | 148 | 150 | 152 |
| September 11, 1988 | June 30, 1992 | April 17, 1996 | February 5, 2000 | November 23, 2003 |
| 154 | 156 |
| September 11, 2007 | July 1, 2011 |

### Tritos series

This eclipse is a part of a tritos cycle, repeating at alternating nodes every 135 synodic months (≈ 3986.63 days, or 11 years minus 1 month). Their appearance and longitude are irregular due to a lack of synchronization with the anomalistic month (period of perigee), but groupings of 3 tritos cycles (≈ 33 years minus 3 months) come close (≈ 434.044 anomalistic months), so eclipses are similar in these groupings.
Series members between 1801 and 2200 :
| February 21, 1803 (Saros 127) | January 21, 1814 (Saros 128) | December 20, 1824 (Saros 129) | November 20, 1835 (Saros 130) | October 20, 1846 (Saros 131) |
| September 18, 1857 (Saros 132) | August 18, 1868 (Saros 133) | July 19, 1879 (Saros 134) | June 17, 1890 (Saros 135) | May 18, 1901 (Saros 136) |
| April 17, 1912 (Saros 137) | March 17, 1923 (Saros 138) | February 14, 1934 (Saros 139) | January 14, 1945 (Saros 140) | December 14, 1955 (Saros 141) |
| November 12, 1966 (Saros 142) | October 12, 1977 (Saros 143) | September 11, 1988 (Saros 144) | August 11, 1999 (Saros 145) | July 11, 2010 (Saros 146) |
| June 10, 2021 (Saros 147) | May 9, 2032 (Saros 148) | April 9, 2043 (Saros 149) | March 9, 2054 (Saros 150) | February 5, 2065 (Saros 151) |
| January 6, 2076 (Saros 152) | December 6, 2086 (Saros 153) | November 4, 2097 (Saros 154) | October 5, 2108 (Saros 155) | September 5, 2119 (Saros 156) |
| August 4, 2130 (Saros 157) | July 3, 2141 (Saros 158) | June 3, 2152 (Saros 159) | | April 1, 2174 (Saros 161) |

### Inex series

This eclipse is a part of the long period inex cycle, repeating at alternating nodes, every 358 synodic months (≈ 10,571.95 days, or 29 years minus 20 days). Their appearance and longitude are irregular due to a lack of synchronization with the anomalistic month (period of perigee). However, groupings of 3 inex cycles (≈ 87 years minus 2 months) comes close (≈ 1,151.02 anomalistic months), so eclipses are similar in these groupings.
Series members between 1801 and 2200 :
| January 10, 1815 (Saros 138) | December 21, 1843 (Saros 139) | November 30, 1872 (Saros 140) |
| November 11, 1901 (Saros 141) | October 21, 1930 (Saros 142) | October 2, 1959 (Saros 143) |
| September 11, 1988 (Saros 144) | August 21, 2017 (Saros 145) | August 2, 2046 (Saros 146) |
| July 13, 2075 (Saros 147) | June 22, 2104 (Saros 148) | June 3, 2133 (Saros 149) |
| May 14, 2162 (Saros 150) | April 23, 2191 (Saros 151) | |